In recent years, as audio/visual communication develops, the demands for file capacity or network traffic grow rapidly. Therefore, immediacy and transmission quality become important in developing electronic devices. These demands continually drive technologies of high speed transmission to progress. In order to speed up signal transmission and shorten the transmission time, some change the coding logic, reduce the signal level or change the transmission mode. To do so, standards for signal attenuation and electromagnetic interference (EMI) become more stringent than ever, such that developers put more efforts on improving the transmission quality and speed of a connector for transmitting signal between electronic components.
However, EMI is generated during signal transmission, and it is a disturbance that will cause any undesirable response, malfunctioning or degradation in the performance of electrical devices near the electronic device or even stop them from functioning. Therefore, how to suppress EMI so as to improve electromagnetic compatibility (EMC) also becomes more and more important.